Electrical cooking-stove



2 Sheets Sheet 1.

(No Model.)

J. V. OAPEK.

ELECTRICAL COOKING STOVE.

No. 424,922. Patented Apr. 1,1890.

N PETUIS. mm-Lnm mr. Wahinglon. n. c.

UNITED STATES PATENT OFFICE.

JOHN V. CAPEK, OF NEIV YORK, N. Y., ASSIGNOR TO HIMSELF, AND EDIVARD II.JOHNSON, OF GREENIVICII, CONNECTICUT.

ELECTRICAL COOKING-STOVE.

SPECIFICATION forming part of Letters Patent No. 424,922, dated April 1,1890.

Application filed October 26, 1889. Serial No. 328.272. (N model.)

To all whom it may concern:

Be it known that I, JOHN V. CAPEK, a citizen of the United States,residing at New York city, in the county and State of New York,

have invented a new and useful In'iprovement in ElectricalCooking-Stoves, of which the following is a specification.

The object of my invention is to produce a practical, economical, andeffective electrical 1o cooking-stove.

Heretofore the use of electricity as a heating medium has been suggestedfor the purposes of cooking; but, so far as I am aware, no practicalapplication of such suggestions has resulted, owing, possibly, to thefailure of inventors to devise a practical device to carry out suchsuggestions.

My invention consists in the devices and combination of deviceshereinafter described,

and particularly set forth in the claims.

In the accompanying drawings, forming a part of this specification,Figure 1 is a perspective view of my electrical cooking stove and asupporting-table. Fig. 2 is a cross-sec- 2 5 'tion thereof, taken on theplane of the line 2 2 of Fig. 1. Fig. 3 is another cross-section takenon the plane of the line 3 3 of Fig. 1. Fig. 4 is a sectional detail ofa modification of the stove-casin Fig. 5 is a bottom plan view of thesupporting-table on a reduced scale. Fig. 6

is a perspective view of the heating-plate, and Fig. 7 is a perspectiveView of the receptacle for the heating-p1ate.

In the drawings, A is the outside wall of the 3 5 stove; B, the insidewall, and C a filling of heatinsulating material-such as asbestus-placedbetween the two walls. It is evident, however, that one of said metalwalls may be dispensed with, and the wall of the stove composed of alayer of insulating material and a single layer of metal. I prefer,however, to employ the construction illustrated. These walls A and B arepreferably of steel, the outer wallsAbeing ornamented to improve theappearance of the 5 stove. These walls maybe shaped to produce anydesired form of stove, and may be provided with lids and doors, as isusual in other forms of stove, the lids and doors being also formed witha lining of heatinsulating ma terial.

D D are square lids fitting into corresponding square holes in the topof the stove, and

E E are round lids fitting into round holes in the square lids D D. Thisarrangement of lids is designed to permit either a square or roundvessel or cooking utensil to be placed into the heating-space of thestove.

In Fig. 4 the hole in the stove-casing is shown provided with a lip F,and a cooking utensil G is shown as provided with a flange II, which,when the cooking utensil is placed in the stove, overhangs the lip F andtends to preserve the heating-space in the stove airtight, and alsoprevents overflows from the cooking utensil entering said heating-space.6 5

The stove is provided with a main door I at one end,which maybe openedto admit the heater and large articles to be cooked. The heater ispreferably of such dimensions that it makes close contact with the innersurface of the side and end walls of the stove. In the door I twosmaller doors J and K are placed, as shown. Each of these doors ispreferably provided with a mica window L on the inner wall closed by aslide M on the outer wall.

The top of the stove is preferablyprovided with a window of mica N,which may be located in a dome 0, said mica window being provided with aslide I. An incandescent electric lamp Q may be located in the dome Sofor the purpose of lighting the interior of the stove for facility ofobservation. Current will be supplied to said lamp Q in-any c011-venient manner. The stove is provided with legs B, so that an air-spaceis left between 8 5 its bottom and the support upon. which it is placed.

S is a table or other suitable support, upon which the stove may beplaced. This table is preferablyprovided with metal tubes T T, to whichthe supply-wires are carried. The tube U is also provided in saidsupport, fora purpose hereinafter to be explained.

The electric heater is composed, preferably, of a platform or backing ofnon-conducting 5 material and a facing or filling of a suitablerefractory conducting material. By this arrangement it is possible toprovide in a great measure against the risk of breaking the conduetingmaterial, which as a rule would be I00 of a brittle character, thebaekingboing made of material to withstand as far as possible the dangerfrom rough handling and accidents. For the backing of the heater Iprefer to employ a plate of fire-brick grooved or furrowedlongitudinally. Iprefer to employ as the refractory conducting materiala compound of graphite, feldspar, and a glass -forming salt. These willbe mixed to form a dough, which is pressed into the grooves of thefire-brick and the whole dried slowly by moderate heat. By theapplication of the current or by further heating, a slight glazing maybe brought out on the surface of the compound, which glazing tends torender the compound firmer, raise its resistance, and lessen the chanceof short-circuiting or shocks by accidental c011- tact. 13y filling thegrooves in the backing to within a short distance of their tops-themethod I prefer-dauger of short-circuiting and shocks is still furtherreduced, as the ridges of fire-brick present a non-conducting surface.Iron cooking utensils may be placed directly upon a heater-plateprovided with ridges extending above the 0011- ducting material withouteffect-ing a short circuit, or if the glazing is carried to the eX- tentof coating the backing as well as the filling of the heater-plate thesame result will be accomplished. Preferablyin miXingI add to thecompound above described some powdered metallic oxide, suboxide of ironbeing preferred on account of its high meltingpoint. The object of thisaddition is to automatically mend the plate should it receive anaccidental crack in use. Should such crack occur, the are resultingwould melt the compound, and it would flow between the edges of thecrackand produce a bridge, thus effecting a connection between the parts.

At each end the heater is provided with a strip of graphitized iron ornickel Y, embedded in a layer Z of moistened graphite. On the under sideof the heater opposite the strip of graphitized iron Y is located astrip of metal at. These two metal strips are secured in place by screwsor bolts Z) Z) passing through them and the heater. A rod 0 passesthrough these plates and through the strips and the heater, and isprovided with a flat spring (7, a nut a working on the threaded portionof the rod 0.

Preferably the heater just described is in closed in a receptacle f, ofsteel, having apertures g cut in the bottom thereof to admit of thepassage of the rods 0 and springs (Z there on, and is held in. suchreceptacle by screwing the nut 6 against the bottom thereof. The

object of this is to still further guard against breakage of the heater.The inside of the bottom of this receptacle is provided with a layer ofinsulating material h. A slide or cover 11, which may be in the form ofa grid, as shown, is preferably used, so that cooking utensils will nottouch any part of the heaterplate. The casing f on its under side isprovided with a rack-bar j, secured to it in any suitable manner. On theunder side of the support S a horizontal shaft 7c is supported inuitable bearings and carries a pinion Z in position to engage with theteeth of the rack j. The shaft 7; is rotated by turning the crank m, andby its rotation causes the elevation of the receptacle f. and heater inthe heating-space of the stove. The heater and its receptacle are heldat any desired elevation by means of a pin m on the crank n, which maybe inserted in any of theseries of holes 0, the shaft 7.; having aslight lengthwise play in its bearings, and the teeth of the pinion Zbeing of sufficient width to permit of this play without disengagementfrom the rack j. The rack j and rods 0 c are of sufficient length topermit the heater and its receptacle, to which they are respectivelyattached, to be elevated to any required height in the heat ing-space ofthe stove without being withdrawn from the tubes T, T, and U. Itisobvious that the devices for conveying current to the heater and forelevating it might be applied directly to it instead of to theheaterreceptacle. p I

Current is conveyed to the heater-plate by wires 2, running to the tubesT T, and to the rods C by the springs (Z, pressing against the tubes,thus insuring good contact. between said wires and said rods 0, nomatter what the elevation of the heater may be in the heating-space.

By the adjustment of theheater in the heating-space of the stove it ispossible to reduce the size of such space when necessary, and thereforeeconomize either current or time required for cooking. It will also beseen that it is possible to cook within the heatingspace of the stove,as by placing the article to be cooked upon the grid 2' or upon a panwhich may be placed on top thereof; and also it is possible to cook atthe same time by inserting utensils through openings in the topof thestove. It will also be seen that by the construction above described itpossible to watch the progress of cooking within the heating-spacewithout being obliged to open the doors thereof, allowing thereby theaccumulated heat to escape.

The arrangement of the layer of non-conducting material between thewalls of the stove permits the heating-space of the stove to become infact a heat-storer, growing hot ter and hotter while the current is on.

lVhat I claim is- 1. The combination, in an electrical cooking-stove, ofa casing, a movable electric heater located therein, an electriccircuit, and means for maintaining the circuit in any po sition of theheater in the stove, substantially as set forth.

2. In an electrical cooking-stove, the combination of a casing, avertically-movable electric heater located therein, mechanism foraltering the position of said heater, and sliding contacts formaintaining the circuit, substantially as set forth.

In an electrical cooking-stove, the combination of a casing, an electricheater 10* cated therein, a rack and pinion for elevating said heater insaid stove, and means for holding said heater at any required height,substantially as set forth.

4. An electric heater for an electric cookstove, comprising a groovedbase of fire-clay and a filling for said grooves of a refractoryconducting material, substantially as set forth.

5. The heating resistance for an electrical cooking-stove, comprising agrooved backing of non-conducting material and a filling for saidgrooves composed of graphite, feldspar, and a glass-forming salt,substantially as set forth.

6. An electric heater for an electric cooking-stove, comprising agrooved backing of fire-brick and a filling of a material of low electrical conductivity placed in said grooves to near their tops,substantially as set forth.

7. An electric heater for an electric cookingstove, comprising a backingof non-conducting material, a filling or facing of a material of lowelectrical conductivity, and a glazing for said conducting material,substantially as set forth.

8. A heating-con duetor for an electric cooking-stove, composed ofgraphite, feldspar, a glass-forming salt, and oxide of iron,substantially as set forth.

9. In an electrical cooking-stove, the combination, with a casing andheater thereof, of an incandescent lamp located within said casing, andwindows in said casin g, substantially as set forth.

10. The combination, in an electrical. cooking-stove, of a heater, areceptacle therefor provided with a layer of insulating material, and agrid located above said heating resistance on said receptacle,substantially as set forth.

11. A casing for an electric cooking-stove, provided with inner andouter metallic walls provided with an inner metallic wall, an outerheat-insulating wall, said walls being broken for lids and doors, andsaid lids and doors being provided with corresponding layers of metaland non-conducting material, substantially as described.

13. A casing for an electric cooking-stove, provided with an innermetallic wall and an outer heat-insulating wall, said walls being brokenfor windows, and said windows hav ing a mica pane on the inner wall anda slide on the outer wall, substantially as set forth.

14. In an electrical cooking-stove, the combination of a casing,amovable electric heater .located therein in close contact with theinner surface of the walls of said casing, an electric circuit, andmeans for maintaining the circuit in any position of the heater in thecasing, substantially as set forth.

15. An electric heater for an electric cookin g-stove, comprising abacking or platform of non-conducting material, a facing or filling ofconducting material, and contacts for said conducting material ofgraphitized iron or nickel embedded therein, substantially as set forth.

16. An electric heater for an electric cooking-stove, comprising abacking or platform of non eonducting material, a facing or filling ofconducting material, strips Y, embedded in layer Z of graphite, stripsto, and bolts securing said strips in place, substantially as set forth.

This specification signed and witnessed this 1st day of October, 1889.

JOHN V. CAPEK.

Witnesses:

WILLIAM PELZER, D. H. DnIscoLL.

